Wiring Products - How to Wire an Automotive Relay - YouTube Click to view on Bing2:04Instructions for wiring a standard automotive relay with descriptions of the pin-out and the schematic. I go over what each contact of the relay is for, and how to understand the schematic that is usually printed on the side of the Author: Wiring ProductsViews: 648K Relay Wiring Diagrams | the12volt Dozens of the most popular 12V relay wiring diagrams created for our site and members all in one place. If you need a relay diagram that is not included in the 76 relay wiring diagrams shown below, please search our forums or post a request for a new relay diagram in our Relay Forum. 12v Relay Wiring Diagram Spotlights | Free Wiring Diagram 12v Relay Wiring Diagram Spotlights - Collections Of Wiring Diagram for Led Driving Lights Awesome Wiring Diagram Driving. Gm Relay Wiring Diagram New Wiring Diagram 12v Relay Refrence Wiring. 12v Relay Wiring Diagram Spotlights Download. Spotlight Wiring Diagram House Fresh 12v Wiring Diagram For A 4 Pin Relay - Best Wiring Diagram China 4 pin relay wiring diagram horn manufacturers and suppliers factory whole meishuo electric 3 sets 12v 40a spst automotive car 4pin relay and 4 wires harness How to wire a 30 40 relay you rh jd1912 diagram pressure China 4 pin relay switch manufacturers and suppliers factory whole meishuo electric 4 pin relay wiring Read More » Automotive Relay Diagram - Del City Numbers of a Relay. Looking at the diagram, we see the pinout of a typical 12V relay. Note that each pin is numbered. 85 and 86 are the coil pins while 30, 87, and 87a are the contact pins. 87 and 87a are the two contacts to which 30 will connect. If the coil is not activated, 30 will always be connected to 87a.